There are known disintegrators (cf., USSR Inventor's Certificate No. 541,497, IPC B 02 C 13/10; U.S. Pat. Nos. 3,771,734, Cl. 241-187, 3,894,695, Cl. 241-55, and British Patent No. 943,319, Cl. B 2A) comprising a housing and grinding rotors inside the housing. The housing has side walls and a cylindrical part making a one-piece construction with one side wall, the other wall being movable. The bottom portion of the cylinder has an outlet pipe, whereas the side wall has an inlet pipe. During operation the ground material is dicharged from the outlet pipe fixed in a structurally predetermined position.
There is also known a grinding apparatus (cf., USSR Inventor's Certificate No. 528,118, IPC B 02 C 21/00) comprising a housing accommodating a rotor with beaters and a separator. The housing includes a cylindrical part and two side walls. The cylindrical part has an inlet pipe and a vertically arranged pipe for evacuating the ground material to the separator. The apparatus can be used only for separation grinding. It needs modifications to carry out once-through grinding.
There is further known a disintegrator (cf., USSR Inventor's Certificate No. 541,497, IPC B 02 C 13/10) which comprises a grinding chamber accommodating rotors with grinding wheels. The housing of the chamber includes a cylindrical part having a pipe for evacuating the material from the grinding chamber and two side walls on one of which there is secured a pipe for charging the material to be ground into the grinding chamber. The cylindrical part of the housing is rigidly connected to one side wall to form an integral arrangement.
The material to be ground is fed to the grinding chamber through the charging pipe to be admitted to the first grinding wheel of the first rotor, and thereafter successively to the rest of the grinding wheels. The material is then thrown away from the rotors toward the inside surface of the cylindrical part of the housing to form a layer of such material sliding down to the outlet pipe to be evacuated from the grinding chamber.
This known disintegrator carries out once-through grinding and the material being ground is discharged from the bottom portion of the housing. In order to effect recycle operation, or to provide separation grinding, it is necessary to make use of auxiliary conveying means to return the material for repeated grinding to crush coarse fraction and collect fine fraction. A switchover from the once-through grinding to recycle grinding is therefore impossible.